CFD Online is an online center for Computational Fluid Dynamics. Services include several discussion forums, a jobs database, a free CFD reference in the form of a CFD-Wiki, a news and announcement forum, a books guide, an events calendar, and a comprehensive annotated link section with pointers to CFD resources around the world. CFD Online's goal is to offer high-quality web services to the CFD community. The site is independent and it is financed mainly by banner-ads.
Today CFD Online is the largest and most popular CFD site on the Internet. During a typical week the web site is visited by more than 78,000 people (unique IP addresses), downloading 488,000 web pages per week. In total there are more than 8,000 web sites around the world with links to CFD Online. In 2017 CFD Online celebrated 23 years of uninterrupted service to the CFD community! CFD Online continues to strengthen its position as the world's leading CFD portal. CFD Online is top-listed by all major search engines and has received many awards over the years.
In 2016 CFD Online had a record growth in web-site traffic and delivered 39% more web-pages than the previous year. This unusually strong growth in 2016 lead to a slight draw-back in 2017 and a reduction in traffic. In 2017 CFD Online delivered 16% fewer web-pages than in 2016. CFD Online still has a very strong traffic and for the second year in a row delivered more than 2 million web-pages per month to our visitors! The number of unique visitors (IP addresses) remained almost unchanged in 2017 compared to 2016. The bar chart above shows the 12-month trailing average of the number of web pages delivered from CFD Online per month over the last 19 years.
Note that these statistics exclude access from robots and common search engines like Google, Bing and Yahoo. This is necessary in order to give a true representation of the traffic from real humans. Otherwise the quickly growing traffic from Google and other search engines robots would completely overshadow human visitors.
Visitors to CFD Online come from typical CFD sites from all over the world. The pie chart below shows the traffic distribution across different top-level domains. Further details about where traffic is coming from can be found in the web server statistics report at https://www.cfd-online.com/Stats/2017/ or in the most recent web-server statistics.
The location of CFD Online’s visitors is similar to last year. A long-term trend is that more and more countries and companies are hiding behind anonymous numerical or network addresses. For example, most explicit traffic from China is now gone. We still have many users from China though, but they are hidden behind anonymous proxies. Traffic from Germany remains very strong and is more than twice as big as the second European country, United Kingdom. On the browser side Chrome has completely taken over as the most popular browser with 54% of all traffic. On the OS side Windows is still the most common OS and Windows 10 adaption has increased from 17% to 26%. Linux maintains its share of 15%. Usage of mobile devices continues to increase and Android + iOS now accounts for almost 9% of our traffic, most likely due to an increased usage of our popular free forum apps. Android usage increases more, from 4% to 6%, whereas iOS grows from 2.5% to 2.7%.
The pie chart below shows the relative number of page-downloads for the different services at CFD Online. In total, the discussion forums are still the most popular section, with 59% of all the page-views. The CFD-Wiki has 20%, the CFD Jobs Database 10%, the Events calendar 3%, the News & Announcement section 3%, and the Links section 1% of all page-views.
The strong growth in traffic to the discussion forums, seen in previous years, has continued also in 2017. CFD Online remains the most popular meeting place on the net for free and independent discussions about CFD. Users seem to prefer the open forums at CFD Online over closed forums run by code vendors. The following services are currently available at CFD Online:
The largest free online CFD news service, with more than 4,500 news and announcements published since 2001. The news section currently has 3,700 unique visitors every month and more than 4,700 people are subscribed to the weekly email news-digest.
The most popular meeting place on the net for people interested in CFD. The forums have more than 640,000 archived messages in 168,000 threads from the previous 20 years.
CFD-Wiki is intended to eventually become the ultimate free CFD reference and text-book. The content is written collaboratively by thousands of users. CFD-Wiki contains more than 550 articles on various CFD related subjects. Many engineers and students use it as a valuable reference.
The links section is very well known in the CFD world and continues to attract many return visitors year after year. It has been the largest collection of CFD links available on the net since it was introduced in 1994. In 2012 a major overhaul of the whole links section was done.
The CFD Jobs Database is the section that attracts most people. The CFD Jobs Database is visited by more than 1,300 job-seekers every day! It is a very good way to recruit CFD experts. The CFD Jobs Database has had about 200 open positions advertised throughout 2017.
The Books Guide is intended to assist students and professionals in finding good CFD books. The guide includes more than 200 books. After the server upgrade we have had problems with incompatibilities with the new hosting system. We hope to solve this soon.
This service is intended to help students and professionals to find CFD related conferences, courses and workshops. The calendar currently includes 33 upcoming CFD events and since the service was opened in 2002 more than 2,800 events have been advertised in it.
The tools section contains online tools useful for CFD engineers and students: Two calculators, a unit converter, a Y+ estimation tool and a tool to convert and estimate turbulent properties.
The feeds section was launched in 2012; it contains aggregated feeds of CFD news-sources, blogs, vendors, jobs and journals. This service has become an important tool to help people stay up to date.
CFD Online is only responsible for the documents on this server, not for any of the external references. All opinions expressed are personal opinions.
CFD Online has throughout 2017 only used SSL/https encrypted traffic. This increases security and makes it impossible to eavesdrop on communication. This is especially important when using public networks. Our servers, installed in June 2015, are working very well. The site is hosted on a virtual server based on Centos KVM technology. The virtual server runs on a dedicated production server with a failover system to quickly switch over to a backup server that stands online ready to take over in case of hardware problems.
Our production server has a Xeon E3-1270v3 CPU, 32GB ECC RAM, and two mirrored RAID1 enterprice SSD disks to ensure a quick and reliable delivery of pages. We have plenty of room to grow and increase our traffic in the future.
